title: Effects of different post-spin stretching conditions on the mechanical properties of synthetic spider silk fibers.
abstract: Spider silk is a biomaterial with impressive mechanical properties, resulting in various potential applications. Recent research has focused on producing synthetic spider silk fibers with the same mechanical properties as the native fibers. For this study, three proteins based on the Argiope aurantia Major ampullate Spidroin 2 consensus repeat sequence were expressed, purified and spun into fibers. A number of post-spin draw conditions were tested to determine the effect of each condition on the mechanical properties of the fiber. In all cases, post-spin stretching improved the mechanical properties of the fibers. Aqueous isopropanol was the most effective solution for increasing extensibility, while other solutions worked best for each fiber type for increasing tensile strength. The strain values of the stretched fibers correlated with the length of the proline-rich protein sequence. Structural analysis, including X-ray diffraction and Raman spectroscopy, showed surprisingly little change in the initial as-spun fibers compared with the post-spin stretched fibers.
authors.affiliation: Department of Molecular Biology, University of Wyoming, Laramie, WY 82071, USA. Electronic address: aalberts@uwyo.edu.
authors.forename: Amy E
authors.initials: AE
authors.lastname: Albertson
authors.forename: Florence
authors.initials: F
authors.lastname: Teulé
authors.forename: Warner
authors.initials: W
authors.lastname: Weber
authors.forename: Jeffery L
authors.initials: JL
authors.lastname: Yarger
authors.forename: Randolph V
authors.initials: RV
authors.lastname: Lewis
mesh_terms: D019840:2-Propanol / Q000737:chemistry; D000595:Amino Acid Sequence; D000818:Animals; D040761:Biomimetic Materials / Q000737:chemistry*; D004586:Electrophoresis; D000431:Ethanol / Q000737:chemistry; D008422:Materials Testing; D055595:Mechanical Phenomena; D008969:Molecular Sequence Data; D047011:Silk / Q000737:chemistry*; D013112:Spiders / Q000737:chemistry*; D013696:Temperature
chemical_list: D047011:Silk; D000431:Ethanol; D019840:2-Propanol
keywords: Argiope aurantia; Dragline; Mechanical properties; Post-spinning; Synthetic spider silk fibers